New study offers theory that MS may begin in brain

May 10, 2018

Wondering 'what if' multiple sclerosis starts in the brain and the immune attacks are a consequence of the brain damage, a new study suggests that a somewhat radical theory may have merit. University of Calgary researchers said their findings suggest there may be something happening deeper and earlier that damages the myelin and then later triggers the immune attacks.

To test their theory, the research team designed a mouse model of MS that begins with a mild myelin injury. In this way, researchers could mirror what they believe to be the earliest stages of the disease. The experiments showed, at least in this animal model, that a subtle early biochemical injury to myelin secondarily triggers an immune response that leads to additional damage due to inflammation. It looks very much like an MS plaque on MRI and tissue examination. They point out that this does not prove that human MS advances in the same way, but provides compelling evidence that MS could also begin this way.

With that result, the researchers investigated treatments to stop the degeneration of the myelin to see if that could reduce, or stop, the secondary autoimmune response. Collaborating with researchers at the University of Toronto, they found that by targeting a treatment that would protect the myelin to stop the deterioration, the immune attack stopped and the inflammation in the brain never occurred.

Currently, MS is considered to be a progressive autoimmune disease. Brain inflammation happens when the body's immune system attacks a protective material around nerve fibers in the brain called myelin. Conventional thinking is that rogue immune cells initially enter the brain and cause myelin damage that starts MS.

Results of mouse model studies sometimes do not translate to humans and may be years away from being a marketable treatment. However, the researchers said their research opens a whole new line of thinking about the disease.

Their findings were published in the Proceedings of the National Academy of Sciences.